History is full of business lessons. And anyone looking to understand disruption could do worse than consider the Vikings, who terrorized Europe for centuries.

While that behavior is not exactly something to emulate, the spirit of rule breaking has its appeal.

“I tell the people I work with that they should be Vikings or pirates,” Bridget van Kralingen, SVP of Industry Platforms at IBM (IBM), told attendees of last week’s Fortune Most Powerful Women Summit in Washington, D.C. And what exactly does that mean? At its essence, it’s about being bold and trying new things. “What’s the worst that could happen?” she asked, emphasizing the importance of bringing experimentation to the 106-year-old tech icon.

Another lesson corporate employees could take from those seafaring raiders: You don’t always have to agree with everyone.

NYSE chief operating officer Stacey Cunningham told the Summit audience that people who have listened in on her company meetings sometimes say, “You’re so mean to each other!” But while those meetings might appear contentious from the outside, she said any disagreement is polite—and is all in the spirit of doing the best thing for the business. “Your intent is so important,” she said.

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Fellow panelist Wendy Clark, CEO of DDB North America, is also a fan of conflict that serves the greater good. The rule, she says, is “Play the ball, not the person, always.”

“Its never about you and me—it’s about the ball and advancing the ball,” she said. Clark insisted that employees must be willing to share any subject or opinion that they want to discuss with her with the entire group. “You have to say it at the table, or you can’t bring it up with me in the bathroom or the hallway…. We have to discuss the un-discussable.”